Constipated baby poop?

Started my 5 month old BF baby on solids after Dr gave the ok. She's only had bananas so far and keep it to no more than 2 tbsp/1oz once a day since we just started this week and I know bananas can cause constipation. I've read that it'll have pebbles but not sure if we're talking bunny rabbit-like pebbles, or if it mixed like this. She doesn't have any additional trouble or straining and it's still very mushy but it's the first time I've seen it with little bits mixed throughout.

Thanks!